An increase in the partial pressure of oxygen causes pulmonary arterioles to , thereby altering to make gas exchange more efficient. constrict; ventilation dilate; ventilation constrict; perfusion dilate; perfusion

1- dilate

2- perfusion

Explanation

when blood pressure increase the arterioles dilate (become smaller) so that cells can absorb the oxygen from the blood easily. perfusion will be altered or slowed down. (The perfusion is the passage of fluid through the circulatory system. )

chert is a sedimentary rock composed of microcrystalline or cryptocrystalline silica. with this little bit of information, you can come to the conclusion that your answer is c.  

explanation:

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